Tip of the Week: Perennial Containers

Here’s a reader’s excellent tip for growing plants in the same container from year to year. Find out how to keep them from getting root bound, plus cut down on the amount of potting soil you have to buy:

I have been growing several plants in the same container for over 10 years, however I do not replace the soil at the top. Instead I slide the plant out of the container and remove up to a third of the compacted soil and root mass, and add fresh soil at the bottom of the container.

On plants such as tropical hibiscus standards, I begin by using a pruning saw to remove about two or three inches from the bottom of the rootball. Then I make three or four evenly spaced vertical slices around the remaining root ball. After teasing several roots free, I remove wedge shape pieces in proportion to the size of the remaining rootball. (Remove no more than a third of the existing soil, including what you initially removed from the bottom of the rootball.)

Then I clean the container, if necessary, and place two to three inches of fresh potting soil in the bottom. Making sure that the hibiscus is set at the proper level, I work soil into the v-shaped spaces. I finish with a 1-inch topdressing of compost.

I usually do this once a year, in the spring as new growth is beginning.